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Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Ecological implications of changes in polychaetes population in a shallow Danish estuary
No full textBurrowing polychaetes are typically the most numerous and active class among macrobenthic infauna in Danish estuaries. Their ecological role is well-recognized and has been often associated with their bioturbating activities. Construction and maintenance of galleries as well as ingestion and defecation displace sediment particles. Ventilation of their burrow irrigates the sediment. These activities transform the environment for other species: from microbes to plants (MS5).Given the important relations between bioturbating polychaetes and their ecosystem, any significant changes in population of a key species may have consequent impact on the ecosystem. The introduction of non-native species is an important vector of change for the often species-poor benthic community of Danish estuaries. Non-native species may bring new functions but also interact with native fauna species.The work presented in this thesis evaluates the effect of population change in size and distribution of 3 polychaete species in a shallow Danish estuary - Odense Fjord: the 2 ecologically important Arenicola marina and Nereis diversicolor and the non-native species Marenzelleria viridis. We focus on the effect of the dynamic of the polychaete population on sediment biogeochemistry and the seagrass Zostera marina.In MS1, the results obtained from different survey indicate that M. viridis was first recorded in 2002 in this estuary and is now present in about 50% of the estuary. The loss of seagrass habitat in some areas of the estuary in late 1990’s and early 2000’s opened bare areas of sediment (5-10km2) where the large bodied A. marina is now present. We also estimate that the total population in A. marina doubled within the last 10 years. There were indications of interaction between N. diversicolor and M. viridis in areas under disturbance (hypoxia or strong bioturbation). To date N. diversicolor remains the prevailing polychaete in this estuary. In the “worst case scenario” assuming that N. diversicolor is completely replaced in areas where the non-native species can survive, there could be a 3-fold reduction in the spatial distribution of N. diversicolor but with a limited effect for its overall population in Odense Fjord.We further investigated how the established non-native M. viridis affect sediment biogeochemistry and compared its effect with that of N. diversicolor in MS4. M. viridis increased sulfate reduction rates in the sediment and created more reduced conditions than N. diversicolor. This was probably caused by the different ventilation and irrigation mechanisms of the 2 species (MS6). M. viridis deep burrow ventilation irrigates the sediment along the wall of the blind-ended burrow which results in the percolation for an average sized M. viridis of about 0.01ml/min of water rich in nutrients and reduced compounds such as sulfide. Provided the large spread of M. viridis in this estuary, the introduction of this non native species in Odense Fjord may have important consequences for the structure of the microbial and infaunal benthic community in Odense Fjord.We evaluated how the feeding or defecating activities of the 3 polychaetes affected seagrass Zostera marina reproductive success through seed burial (MS2). The 3 worms buried seeds either directly by grabbing the seeds (N. diversicolor) or indirectly by covering seeds with their fecal pellets. The emergence of the seedling is only possible if the seed is positioned within the top 6 cm of the sediment (MS3). We estimate that in areas where the abundance of A. marina >8 ind m-2, the eelgrass reproductive success may be compromised. The recent increase in the distribution of A. marina most probably reduced the opportunity for eelgrass to recolonize this estuary
Ecological implications of changes in polychaetes population in a shallow Danish estuary
No full textBurrowing polychaetes are typically the most numerous and active class among macrobenthic infauna in Danish estuaries. Their ecological role is well-recognized and has been often associated with their bioturbating activities. Construction and maintenance of galleries as well as ingestion and defecation displace sediment particles. Ventilation of their burrow irrigates the sediment. These activities transform the environment for other species: from microbes to plants (MS5).Given the important relations between bioturbating polychaetes and their ecosystem, any significant changes in population of a key species may have consequent impact on the ecosystem. The introduction of non-native species is an important vector of change for the often species-poor benthic community of Danish estuaries. Non-native species may bring new functions but also interact with native fauna species.The work presented in this thesis evaluates the effect of population change in size and distribution of 3 polychaete species in a shallow Danish estuary - Odense Fjord: the 2 ecologically important Arenicola marina and Nereis diversicolor and the non-native species Marenzelleria viridis. We focus on the effect of the dynamic of the polychaete population on sediment biogeochemistry and the seagrass Zostera marina.In MS1, the results obtained from different survey indicate that M. viridis was first recorded in 2002 in this estuary and is now present in about 50% of the estuary. The loss of seagrass habitat in some areas of the estuary in late 1990’s and early 2000’s opened bare areas of sediment (5-10km2) where the large bodied A. marina is now present. We also estimate that the total population in A. marina doubled within the last 10 years. There were indications of interaction between N. diversicolor and M. viridis in areas under disturbance (hypoxia or strong bioturbation). To date N. diversicolor remains the prevailing polychaete in this estuary. In the “worst case scenario” assuming that N. diversicolor is completely replaced in areas where the non-native species can survive, there could be a 3-fold reduction in the spatial distribution of N. diversicolor but with a limited effect for its overall population in Odense Fjord.We further investigated how the established non-native M. viridis affect sediment biogeochemistry and compared its effect with that of N. diversicolor in MS4. M. viridis increased sulfate reduction rates in the sediment and created more reduced conditions than N. diversicolor. This was probably caused by the different ventilation and irrigation mechanisms of the 2 species (MS6). M. viridis deep burrow ventilation irrigates the sediment along the wall of the blind-ended burrow which results in the percolation for an average sized M. viridis of about 0.01ml/min of water rich in nutrients and reduced compounds such as sulfide. Provided the large spread of M. viridis in this estuary, the introduction of this non native species in Odense Fjord may have important consequences for the structure of the microbial and infaunal benthic community in Odense Fjord.We evaluated how the feeding or defecating activities of the 3 polychaetes affected seagrass Zostera marina reproductive success through seed burial (MS2). The 3 worms buried seeds either directly by grabbing the seeds (N. diversicolor) or indirectly by covering seeds with their fecal pellets. The emergence of the seedling is only possible if the seed is positioned within the top 6 cm of the sediment (MS3). We estimate that in areas where the abundance of A. marina >8 ind m-2, the eelgrass reproductive success may be compromised. The recent increase in the distribution of A. marina most probably reduced the opportunity for eelgrass to recolonize this estuary
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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